JPS59100475A - Supporting device of transfer material - Google Patents

Abstract

PURPOSE:To use both hands freely in drawing-out operation and to prevent damage to a photosensitive body by allowing a transfer material supporting drum to be taken out of the photosensitive body only when they are separated from each other, and separating them forcibly during the drawing-out operation. CONSTITUTION:When a grip 6c is turned up to a stop pin 10 counterclockwise during drawing-out operation, a cam 6b abuts on a roll 5b to turn a support plate 7 and the transfer material support drum 4 slightly clockwise; and members are moved to dotted-line positions shown by symbols 6b, 5b, 4a, 4, etc., and the drum 4 separates from the photosensitive body D. At the same time, a rising member 8 does not engage a lock member according to the turning of the cam 6b, a rod body 6a, etc. Then, a side plate 3, a frame and the drum are drawn out. When the drum is drawn out slightly, the member 8 engages the corner part 9a of a member 9 to inhibit its turning and the cam 6b, therefore, operates on the roll 5b continuously, so the grip 6c is freed from the hand at this time to draw out the drum continuously.

Description

Detailed Description of the Invention (a) Purpose of the Invention This invention provides an image forming apparatus such as an electrostatic copying machine and a printer;
In particular, it relates to the transfer material supporting device.

Forming a transferable image (1) An image forming apparatus configured to transfer an image by bringing a cylindrical transfer material support drum supporting a transfer material close to a photoconductor is particularly useful when the image is transferred repeatedly to the same transfer material. Conventionally, it has been used in color image forming apparatuses that perform transfer.

In such an image forming apparatus, a transfer material support drum is pressed against a photoreceptor with a moderate pressure for transfer (the transfer material support drum is swingably disposed, and in its natural state, the drum is not photosensitive). There are known devices that are configured to come into contact with the body or devices that are configured to come into contact with a photoreceptor using an elastic member.

In this way, when the transfer material support drum is brought into contact with the photoreceptor during image formation, when the transfer material support drum is removed from the image forming apparatus during maintenance, inspection, or repair, etc., it should be kept as it is. If it is pulled out in the axial direction of the drum, there is a risk of damaging the photoconductive layer on the surface of the photoreceptor. Of course, if the photoreceptor and transfer material support drum are separated in the direction orthogonal to the linear contact portion, the above-mentioned fear will not occur, but due to the mechanism arrangement within the image forming apparatus? It is easy to understand that it is virtually impossible to take measures such as -.

Before taking the drum out of the image forming apparatus, make sure to separate it from the photoreceptor and then take it out in the direction of its axis.
IIJ has already been proposed.

FIG. 1 shows an example of this type of well-known printing press, and is a perspective view showing a part of the transfer material support drum pulled out from an opening ``a'' in a side plate 1 of the main body of the image forming apparatus.

The transfer material support drum 4 includes a pair of side plates 3 (only one of which is shown in the figure) and a connecting rod 2 that connects the both side plates □.
a, 2'b', '2'''c and 2d.A rod 5a is placed above the frame, and a transfer plate is placed at both ends of the rod 5a. Rollers 5b are attached outwardly from both end faces of the material support drum 4.-A support plate 5c is fixed to each roller 5b along the end face of the transfer support drum, and is inserted into the side plate 3. The pin 7 extending inward of the frame is pivotally connected to the support plate 5c.Also, the shaft 4a of the transfer material support drum 4 is also pivotally connected to the support plate 5C, so that the drum 4 is ultimately connected to the support plate 5c. It is pivotally supported so that it can swing freely with 7 as the center.

However, by placing the transfer material support drum 4 at an appropriate position within the swing range relative to the photoreceptor (not shown) in the image forming apparatus, the transfer material supporting drum 4 can be held by its own weight. It is often possible to press the photoreceptor against the photoreceptor. Of course, it is possible to adjust the pressing action against the photoreceptor by adding an elastic member as necessary.

A rod 6a is further pivotally attached to the side plate 3, and the rod 6a
5. The cam 6b is located at the position corresponding to b.
The rod 6a extends outward beyond the side plate 3, and a handle 9C is attached to the end.

As can be seen from FIG. 1, the cam 6b is in contact with the lower side of the roller 5b, and in this state it does not prevent the transfer material support drum 4 from being maintained in its operable position. .

Before taking out the transfer material support drum 4 to the outside, the handle 6C is rotated to rotate the cam 6b in the direction of the arrow in the figure.The cam comes into contact with the roller 5b and pushes it away. It will be rotated in the direction of arrow B. Along with this, the support plate 5c integrated with the roller 5b also rotates, and therefore the transfer material support drum 4 supported by the support plate 5c also rotates and is separated from the photoreceptor, so that the state is maintained. Just pull it out.

In such a known device, the handle 6C is operated manually, so there is a possibility that the handle 6C may be manually operated, not only if you forget to separate the transfer material support drum 3 from the photoreceptor and try to carry out the unloading operation, but also if the handle 6C is operated for some reason during transportation. If the drum 4 were to rotate so that the drum 4 came into contact with the photoreceptor, the photoreceptor would be damaged, and a very simple mistake on the part of the operator would have serious consequences.

The present invention has been made in view of the current situation, and when the transfer material support drum is taken out, it is necessary to take it out unless the drum is brought to a position away from the photoreceptor beforehand. It is impossible to remove the drum from the photoconductor during the process of pulling it out, and the drum remains in a stable state separated from the photoconductor. It is an object of the present invention to provide a transfer material support device that reliably prevents contact between the transfer material and the transfer material and allows the two to contact each other only when they reach a predetermined position.

(B) Structure of the Invention FIG. 2 is a side view of a main part of a transfer material supporting device showing an embodiment of the present invention, and an opening 1a formed in a side plate 1 of the main body of the image forming apparatus is provided with a side plate 3 of the transfer material supporting device. The transfer material support drum 4 is maintained in a predetermined position by engaging with the transfer material support drum 4. The drum 4 is pivotally connected to a support plate 5C which is pivotally supported by a pin 7, and a cam 6'O is removably disposed on a roller 5b which is integrally provided with the support plate 5C. The structure in which the cam 6'b is operated by the handle 6C is the same as the known structure shown in FIG.

In such a device, as shown in FIGS. 2 and 3, in the device of this embodiment, the inner surface of the main body side plate, the cam 6b
Attaching the locking member 9 near the cam 6b
A rising member 8 is provided inside the locking member over almost the entire length of the rod 6a on which the rod 6a is mounted. In addition, a stopper pin 10 for regulating the rotation range of the handle 6C is provided at a suitable position inside the side plate 3 of the frame.
. 1. When the transfer cylinder support drum 4 is in its operating position, two members 8 (1) and 8 (2) are provided in a position to engage with a locking member 9 provided on the side plate 1 of the main body to separate the drum from the photoreceptor. It is arranged so that it takes a disengaged position when it is rotated.

FIG. 3 is an end view with the frame removed to explain the rotational movement of the transfer material support drum, and the drum 4 is in pressure contact with the photoreceptor at the position indicated by the solid line in the figure. The cam 6b does not exert any action on the rollers 51), and each member is in equilibrium.

As mentioned above, at this time, the rod 6a supporting the cam 6b
The rising member 8 attached to the holder is arranged in such a manner that it overlaps the locking member 9 when viewed from the end face. Therefore, even if you try to pull out the drum in this state, that is, in a state where the photoreceptor and the transfer material support drum L are in contact with each other (this means displacing it toward the front in the direction perpendicular to the plane of the paper), it will not engage with the rising member 8. It is impossible to pull out the drum due to the contact with the stop member 9.

When the handle 6C is rotated counterclockwise in the figure by 10 inches of the stopper pin, the cam 61 comes into contact with the roller 5b, and the roller 5b, and therefore the support plate 7 and the The transfer material support drum 4 pivotally mounted thereon is rotated slightly clockwise gr to move these members (6b), (5b), (4,a,).

The strainer drum 4 is moved away from the photoreceptor at the position indicated by the dotted line (4).

At the same time, with the rotation of the cam 6b, rod 6a, etc., the rising member 8 is also rotated to the position shown in FIG. Next, the transfer material support drum can be easily pulled out together with the frame including the side plate 3.

Note that when this is pulled out a little, the rising member 8 engages with one corner 9a of the locking member 9 and prevents its rotation, and therefore the cam 6b continues to act on the roller 5b. After that time, even if you remove your hand from the handle 6C, you can continue to perform the pull-out operation.

(c) Effects of the invention As explained above, in an image forming apparatus in which a transfer material is wound and supported on a transfer material support drum disposed close to a photoconductor to perform transfer, this drum is used in an image forming apparatus. When attaching and detaching the transfer material from the photoreceptor, the transfer material support drum cannot be lifted and suspended unless it is separated from the photoreceptor, and furthermore, during the operation of pulling out the drum, the drum is forcibly maintained separated from the photoreceptor. 1"! Since it can be pulled out, there is no need to hold the handle or the like, and both hands can be used freely, which definitely avoids the risk of damaging the photoreceptor. Of course, the transfer material support drum When installing the drum into the image forming apparatus, I used both hands freely to keep the drum and photoreceptor separated. Also, with the mounting, the drum could only come into contact with the photoreceptor once it had reached a predetermined position. be.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a part of a known transfer material support drum pulled out from an image forming apparatus, and FIG. 2 is a diagram showing the relationship between the transfer material support drum and related parts according to an embodiment of the present invention. FIG. 3 is an explanatory view showing the operation of the transfer material support drum shown in FIG. 2. ]... Image forming device, 3... Side plate, 4... Transfer material support drum h, 5b... Roller, 5c... Support Fi[,
6b-, cam, 6c...handle, 7...bottle, 8...
- Standing member, 9...locking member, 10...stopper.

Claims (1)

[Scope of Claims] A transfer material supporting drum that is in pressure contact with an image carrier in a state where it can freely come into contact with and separate from it, and a cam that forcibly separates this drum from the photoreceptor, comprising: means for always preventing the drum from being pulled out when the support drum is in a predetermined position, and for maintaining the transfer material support drum in a state separated from the image bearing member that can be pulled out by operating the cam to pull out the drum; A transfer material support device.